问题 填空题

身高为1.65m的小明同学,站在竖直放置的平面镜前2m处来实际体验平面镜成像的特点,则他在镜中的像的高度是______m,像距离平面镜______m,当他后退1m,像离他本人的距离是______m,像的高度______m.

答案

因平面镜成像时像和物体形状、大小相同,所以身高为1.65m的小明同学,则他在镜中的像的高度也是1.65m;

因平面镜成像时物距等于像距,所以小明同学站在竖直放置的平面镜前2m处时,此时物距为2m,则像距也为2m;

当后退1m,此时物距为2m+1m=3m,像距也为3m 像与人的距离为物距与像距之和,为6m,像的高度不变,仍然为1.65m.

故答案为:1.65;2;6;1.65.

阅读理解

阅读理解。

    Once upon a time, there lived a rich man. He had a servant (仆人). He and the servant loved wine (酒)

and good food very much. Each time the rich man left his home, the servant would drink the wine and

eat up all the nice food in the house. The rich man knew what his servant did, but he had never caught

his servant doing that.

    One morning, when he left home, he said to the servant, "Here are two bottles of poison (毒药) and

some nice food in the house. You must take care of them." With these words, he went out.

    But the servant knew what the rich man had said was untrue (假的), after the rich man was away

from his home, he enjoyed a nice meal. Because he drank too much, he was drunk and fell to the ground.

When the rich man came back, he couldn't find his food and his wine. He became very angry. He woke

(叫醒) the servant up. But the servant told his story very well. He said a cat had eaten up everything. He

was afraid to be punished (被惩罚), so he drank the poison to kill himself.

1. In the story, _____ liked wine and good food very much. [ ]

A. the rich man

B. the servant

C. both A and B

D. neither A and B

2. The rich man knew that it was _____ that drank the wine and ate up all the nice food.[ ]

A. the cat

B. himself

C. nobody

D. the servant

3. The rich man told the servant that there was poison in the two bottles, because _____. [ ]

A. there was in fact poison in the bottles

B. he did not want the servant to drink his wine

C. he wanted to kill the cat

D. he wanted to kill the servant

4. In fact _____ ate all the nice food and drank the wine.[ ]

A. the servant

B. cat

C. the rich man

D. nobody

5. From the story, we know that the servant is very _____. [ ]

A. lazy

B. bad

C. clever

D. kind

选择题